Audio Research DS 450 amp......thoughts

....that's what I'm looking for, thoughts on this class D amp from this tube giant. Some people like like it.....what do YOU think if you have heard it
I came very close to buying it. My local dealer didn't have the DS450 for me to demo, but he did play the DS225 for me with some Proac speakers. I thought it sounded impressive, but in the end, with so many quality SS amps out there, I just didn't want to drop that kind of money on a class D amplifier. (Ended up buying a simaudio evolution W8). During my research, I did get a chance to speak to one of the head guys at ARC (forget his name), and they are quite proud of their DS amps.
I purchased the DS450 (along with the LS27) about 6 weeks ago. Did extensive listening including McIntosh and Ayre. Found the transparency, musicality and soundstage on the DS better to my liking. The McIntosh had a deeper bottom end - but not by much.

I'm driving a pair of Revel Salon 2s with the DS450 and I'm very happy with the results so far.

Yes, I've read that recently in the TAS. Paired with the Ref 5 or LS27, that should be a nice combo.
I'm using a Ds225 on Magnepan 1.7s and soon on 3.7s. I find that the amp is very transparent and really reacts to any upgrade connected to it. I've grown to like the amp after selling my ARC SD135. Its taken some time to understand this amp, It has many qualities, but get the best fuse, power cord, cables and front end you can afford as the DS series amps are VERY unforgiving and will fault towards bright / grainy with less refined stuff surrounding it, but as it's said, "Don't shoot the messenger".
I'll be interested in your thoughts on the 3.7 paired w/ the DS225. I currently run a VT200MkI w/ a Ref3 on the 3.7s. I have considered purchasing a DS450 but have been uncertain about trading my tubes for a class D amp.
Keep your VT200.
That amplifier throw one of the greatest stereo soundstages in the business.
I tried some class D amps incl. ARC 150.2 and 300.2 (still own it), but I never got satisifed with the timing and timbre of the upper registers.
The technology simply can't compete with traditional amplifers.
My 300.2 is a great amplifier for driving the servobass of my Infinity Epsilons however.
For higher registers ?
No thanks...
Replacing one of the greatest as VT200 are?
No, not a chance IMHO.

PS. Using VT-150SE for the planar drivers of my Infinity Epsilons where the do a fantastic job.
Also, I've heard said it's the first time an arc amp gives the maggies deep bass
....I would be matching this amp with a pair of Sonus Faber Cremona M's with a Esoteric front end. Thoughts ????
Thanks for the input. I've been very pleased w/ the VT200 and I've owned it since 03 w/o only one re-tube at ARC, but the care and feeding of 16 6550s is always on my mind.
Sorry, OP, back to you! could be a great matchup.
From what I've heard of Sonus Fabers, always seems slightly dark, and could use the detail and snap of the DS series. Any chance of trying first?
IMO...Do not use ANY class D amp fullrange.
The technology simply can't compete with similar priced traditional class A or AB amplifier.
I have experience with Tripath, Hypex and IcePower.
All have failed to impress in the long run.

Esoteric make excellent products.
SF make colored products to my ears.
Still haven't heard a SF loudspeaker that are truly transparent and neutral.
But that is also a matter of personal preference.
I simply hate colored loudspeakers.

....thanks Flex 2 for yuor comments on the SF's...anyway....the more I read... I don't see where the ARC DS450 is a '' true '' class D amp.....
Cut from Audio Researchs website:

"The output stage is a high-speed pulse-width modulated (analog) switching design that also builds on the proven formula in the DSi200, but with twice the number of 500W power-mosfet output devices in each channel. With a 400 kHz switching duty cycle, the output stage stays cool under the toughest loads."

So it's a true class D amplifier.

If a amplifier should have a chance to let the upper registers and treble through in a fairly unharmed way the -3dB point should be 200KHz or higher.

DS450 have it's -3dB at 45KHz while 300.2 have it's -3dB point at 30KHz.
A slight improvement, but not enough in my opinion.
When they reach swithing frequencies at 2-5 MHz and have -3dB point in the 200-500KHz range there might be a chance that a class D amplifier can compete with a good traditional amplifier.

Don't we all remember how the first CD-players with brickwall filters sounded like compared to vinyl ?
Real bad.
I would say that the same can be said about class D amps compared to traditional amplifier technology.
It simply lacks air and precision in the soundstage which also are compromised and in your face.
Timbre is lousy and it's very hard to hear any acoustic instrument as it was recorded.

Audio research's efforts still are some of the best in the market, but the technology itself are too undeveloped at the moment (for fullrange use).

May want to give it a listen. I did a comparison with Ayre and McIntosh. The DS450 did extremely well.


I will absolutely give it a listening when I get the chance, and try to keep an open mind.
Audio research are and will always be one of my favourite brands so I will always listen to their products when I get the chance to do so.
Few other brands have been able to recreate the musical event as natural and vivid as ARC's more successful designs.
Thank you for your reponses....what must also be take into consideration is that this amp is $8,000. It is not inexpensive however you want to compare.
Before you bash a product you should at least listen to it in a familiar environment. and in the case of the new ARC digital amps make sure they've had several hundred hrs to burn in.I have the Dsi 200 and it's evolved into an outstanding amp.
This practice is a disservice to all envolved.
I you read my input a little better you will find that I don't bash DS450 in particular.
I bash the principle of class D amplifiers in general.
Read again and learn some about why the technology can't compete with traditional amplifier technology.
I hear a lot of different amplifiers, and until now I haven't heard any class D amplifier that sound really good.
And please remember, that is MY experience.
Yours might be different.
Why let the facts get in the way of expressing an opinion? That's why the internet was invented, right? :)
"I don't bash DS450 in particular. I bash the principle of class D amplifiers in general."

I'm not sure how anyone can make a statement like that seriously. Everyone is entitled to say whether or not they like a particular amplifier. But to claim that an entire class of amplification is poor is a gross generalization. Audio Research is too well-regarded a company to waste their time, first with the 150.2 and 300.2 amps, and now the entire DSx series, if they don't believe that class D amplifiers can be at least the equal of other types of amps. The same can be said of Mark Levinson (whose newest amp is class D), Rowland, W4S, Bel Canto, Nu Force, and many other manufacturers. It's just become either too easy, or the "in thing" to claim that an amplifier simply doesn't cut it, after all, it's a class D amp. Critique individual amplifiers if you will, but don't generalize.
How many class D amps do you need to hear before making a statement about there sound . I don't like the principle either but the three iv'e listened to are not enough to judge a technology on .
I thought the DS 450's sounded quite good considering the price . When I checked the specs , I found they didn't double down into 4 ohm's in fact stayed the same as 8 ohm's .
Levinson claims there new amp's including the #53 are not class D , if you Email them they will send you a white paper with details .
Since it is my experience I can make a statement like that.
I have heard most of the "high-end" class D amps around.
Spectron, Rowland, Nuforce, Bel Canto, Embla etc, etc and none of them have been able to create a solid soundstage that I expect from a truly "high-end" amplifier.
Sooner or later we will see switching frequencies that allow for output filters at 200 Khz or higher, but until that happends the class D technology will be inferior to traditional amplifier technology.
...and please remember, that is MY experience so far so please don't tell me what I can't say or not...

If you have a different opinion please express it.
Perhaps you can mention a class D amplifier that can compete with a Audio Research VT-200 regarding soundstage and honesty to the recorded music ?
Because that was the original question that started this small debate...
Let's lower the temperature of this discussion a bit. My objection was simply that if an entire amplifier technology is inferior, I don't understand why a fairly large number of respected manufacturers keep pursuing it.

My own experience is a lot lower-priced than many of yours. Over the years I've owned Quad 303, 405, BGW 250, ARC D90B, and now an ARC 150.2 amplifier. None come anywhere close in price to an $11K (when it was discontinued) ARC VT200. So I have no opinion on how any of the amps I've owned compare to a VT200. If I can make a gross generality of my own, I would expect an $11K amp to outperform any of the roughly $3K amps I've owned. That has nothing to do with technology, just my belief that in general you get what you pay for. From my own experience, all I can say is that I feel the 150.2 drives my Maggie 1.6s better than the D90B did, and paired with an LS17, I enjoy the music. So I would say my own class D experience is positive, within the price parameters of my own equipment.

The original question asked for opinions on the DS450 (the VT200 entered the thread a bit later), and since I haven't heard it, I stayed out of the discussion until the general condemnation of class D came up. Obviously, since I own and enjoy a class D amp, I have a desire to defend the technology to some degree. What I find somewhat contradictory is that a number of reviewers (regardless of whether one likes reviews or not) have been positive about at least some class D amps. I believe the Nuforce amps have been on Stereophile's class A (now that's confusing!) components list, in Soundstage's review of the ARC 150.2 the reviewer specifically recommended it for Maggies, and in TAS, Tom Martin actually purchased his review 300.2. I haven't seen any reviews of the DS450 or DS225; IIRC the review of the DSi200 was positive. Now none of this is definitive in any way, but it suggests that there are at least some who aren't negative about all class D amplifiers.

As a quick aside, my understanding is that Levinson's #53 is a switching amp, and I don't know of any class for switching amplifiers other than "D." I would suggest (without any factual support) that it is precisely the overall negative connotation that some have for class D which is why Levinson argues that their amps are not class D. That may also be why ARC called their 150.2 and 300.2 amps "class T" (after Tripath, the manufacturer of the chip) rather than class D, and I'm not sure what they are calling their DSx series.
A lot of reviewers get blended by the emperor's new cloths.
For example:
PS Audio HCA was one of the first class D amps that reached a class A rating at Stereophile.
The words was "tubelike" "revolutionary" the best of the best and had to be considered regardsless of price.
Today reality have catch up, and if you even can sell one of these amplifiers you will only get a few hundred dollars.
I used to own one, and soon discovered that it didn't sound very well, so it was removed from my home after 4 months.

I used to own a 150.2 too.
The reason for buying it was for driving a pair of Magnepan 3.5R in my TV system, and the only reason for selecting 150.2 was for the posibility to keep it on permanently without the power consumption and because I really like ARC as a company.
It was paired with ARC LS12 as a linestage (lovelly sound from this little linestage).
I soon replaced the 150.2 with a Restek Tensor and the improvment was enormous.
The soundstage quadrupled in size and suddenly all complex acoustic instruments was rendered with full size and sounded as the real music event.
So sorry if I recommend that you try a different power amp that isn't a class D amp.

Sorry for Tom Martins decision to select 300.2 unless he use it for bass only as I do with my 300.2
...and of course I have tried my 300.2 for full range operation.
Does it sound good and cast a high-end soundstage?
I'm sorry but it doesn't.
It's dynamic and sound powerful, but it can't let the music through in a unharmed way.

From my point of view switching technology is best kept for powersupply service and leave the amplifing circiutry to traditional amplifing technology.
Two companies that have come to the same conclusion are Linn and Halcro.
Both have got some nice reviews from the press too.

But I expect class D technology to keep getting better and better and eventually it can compete with traditional amplifiers.
I will keep listening to them.
This is what I have found until today...

Do you remember the seventies when tube amplification almost died out because of the new revolutionary transistor technology ?
Today we know better...

I don't think we will see a similar evolution with class D amplifiers, but be aware of the problems with the basic technology that class D amplifiers are built on.
The industry will eventually solve them, but from my point of view it will take some years from now.

Regarding the "T" class that ARC state it depends on the fact that it is a variation of class D amlifier with a variable switching frequency, but make no mistake, it's still composed of a comparator that compare a triangular wave with the signal and produce a PWM signal to drive the switching output transistors.
Just to vary the triangular wave switching frequency according to the demand of power will not make it a none class D amplifier.

There are some other versions of switching amplifier technologies (E/F/G/H), and there have been some examples of class G and H in the market. Usually for our portable audio devices.
E and F is for high frequencies and not suitable for audio.

Please read more here if you want:
There is one instrument that can disprove all the theory's in the world,and that is the Human Ear!
I bought my Ds 450 8 months ago along with LS 27 to drive Sophia III speakers. At 1st the 450 left me wanting, but after the longest burn-in necessary in my experience, 600+ hrs. the 450 allowed all of great sound from the LS 27 to flow through and I am now very satisfied from various aspects.
I had a chance to compare the Class D Audio Research integrated VS. Ayre V5xe with matching pre amp through Maggie 3.7s. The Ayre had noticably greater soundstaging and detail resolution.
The ARC had a wetter, less dry sound with more tonal density and better bass extension on the Maggies.
I just got one of the last factory fresh DS450's. It replaced my HD220. (Long story)

 Anyhow, im using the stock arc power cord from hd220 is it was already there sitting on the rack and the new power cord seems identical 12 gauge 20
amp. I also used an S.R. Quantum red fuse in the 220. I'm planning on trying the newly released quantum black. Unfortunately I can't use the old red fuse from the 220 because it's 8 amp and the 450 calls for 10 amp. 

what fuse and power cord are you using? I'm still breaking mine in obviously. It has about 72 hours on it and it's improvement has not been linear. Almost like my Morrow cables. I'm just curious as to the improvements you heard with this particular amp. So far, with everything stock, it has a great sound! I'm not really missing the 220. It is much more robust, images as well or better than the 220 with the upgraded fuse, and seems smoother even though it's class D!  

This is my first class D amp. I'm not sure why everyone doesn't like class D. Maybe this is a testament of how good the ds450 is compared to other class D Amps. 
Well, a few don't like them or there wouldn't be so many for sale on the used market.........I have to wonder where we go from here........
Personally instead of getting a D class amp from Audio Research,  I would look for a good D400MKIII which are generally less than 2 grand any more.  200/400/800 watts a side at 8/4/2 ohms and can drive virtually anything, or at least have no trouble driving my Maggie 20.7s.

Bough my first one new then added a second when I bi-amped my MG 3As and no not going to or trying to sell one  LOL